Web 2.0 is a term describing changing trends in the use of World Wide Web technology and web design that aims to enhance creativity, secure information sharing, collaboration and functionality of the web. Web 2.0 concepts have led to the development and evolution of web-based communities and its hosted services, such as social-networking sites, video sharing sites, and folksonomies. The term became notable after the first O'Reilly Media Web 2.0 conference in 2004. Although the term suggests a new version of the World Wide Web, it does not refer to an update to any technical specifications, but to changes in the ways software developers and end-users utilize the Web.

Alluding to the version-numbers that commonly designate software upgrades, the phrase "Web 2.0" hints at an improved form of the World Wide Web. Technologies such as weblogs (blogs), wikis, podcasts, RSS feeds (and other forms of many-to-many publishing), social software, and web application programming interfaces (APIs) provide enhancements over read-only websites.

Characteristics

The idea of "Web 2.0" can also relate to a transition of some websites from isolated information silos to interlinked computing platforms that function like locally-available software in the perception of the user. Web 2.0 also includes a social element where users generate and distribute content, often with freedom to share and re-use. This can result in a rise in the economic value of the web to businesses, as users can perform more activities online.

Web 2.0 websites allow users to do more than just retrieve information. They can build on the interactive facilities of "Web 1.0" to provide "Network as platform" computing, allowing users to run software-applications entirely through a browser. Users can own the data on a Web 2.0 site and exercise control over that data. These sites may have an "Architecture of participation" that encourages users to add value to the application as they use it. This stands in contrast to very old traditional websites, the sort which limited visitors to viewing and whose content only the site's owner could modify. Web 2.0 sites often feature a rich, user-friendly interface based on Ajax, Open Laszlo, Flex or similar rich media.

Technology overview

Web 2.0 websites typically include some of the following features/techniques that Andrew Mcafee used the acrynom SLATES to refer to them:

Ajax has prompted the development of websites that mimic desktop applications, such as word processing, the spreadsheet, and slide-show presentation. WYSIWYG wiki sites replicate many features of PC authoring applications. Still other sites perform collaboration and project management functions. In 2006 Google, Inc. acquired one of the best-known sites of this broad class, Writely.

Several browser-based "operating systems" have emerged, including Eye OS and You OS. Although coined as such, many of these services function less like a traditional operating system and more as an application platform. They mimic the user experience of desktop operating-systems, offering features and applications similar to a PC environment, as well as the added ability of being able to run within any modern browser.

Internet applications

Rich-Internet application techniques such as AJAX, Adobe Flash, Flex, Java, Silver light and Curl have evolved that have the potential to improve the user-experience in browser-based applications. The technologies allow a web-page to request an update for some part of its content, and to alter that part in the browser, without needing to refresh the whole page at the same time.

Server-side software

Functionally, Web 2.0 applications build on the existing Web server architecture, but rely much more heavily on back-end software. Syndication differs only nominally from the methods of publishing using dynamic content management, but web services typically require much more robust database and workflow support, and become very similar to the traditional intranet functionality of an application server.

Client-side software

The extra functionality provided by Web 2.0 depends on the ability of users to work with the data stored on servers. This can come about through forms in an HTML page, through a scripting-language such as Javascript / Ajax, or through Flash, Curl Applets or Java Applets. These methods all make use of the client computer to reduce server workloads and to increase the responsiveness of the application.

Advocates of "Web 2.0" may regard syndication of site content as a Web 2.0 feature, involving standardized protocols, which permit end-users to make use of a site's data in another context (such as another website, a browser plugin, or a separate desktop application). Protocols which permit syndication include RSS (Really Simple Syndication — also known as "web syndication"), RDF (as in RSS 1.1), and Atom, all of them XML-based formats. Observers have started to refer to these technologies as "Web feed" as the usability of Web 2.0 evolves.

The analysis of the economic implications of "Web 2.0" applications and loosely-associated technologies such as wikis, blogs, social-networking, open-source, open-content, file-sharing, peer-production etc has also gained scientific attention. This area of research investigates the implications Web 2.0 has for an economy and the principles underlying the economy of Web 2.0.

Organizations could make use of these principles and models in order to prosper with the help of Web 2.0-like applications such as the models where masses of consumers, employees, suppliers, business partners, and even competitors co-create value in the absence of direct managerial control.

Web 2.0 has started a wave of innovations that is giving rise to new business models leveraging the power of internet and social networking. It has made it easier to syndicate data from various sites and display it in the desired manner. The social networking sites such as facebook and myspaces already have huge number of registered users, contributing to the global repositories of knowledge and data.

Web 2.0 has transformed the static HTML web pages into powerful dynamic pages that source their content from different global repositories of data and display it for the users in customized form "on demand". This information revolution has just set-in and will surely change the way, people work, communicate and conduct their businesses in the years to come.